Tractor.



G. C. JETT.

TRACTOR.

APPLICATION men JAN.30, 191s.

Patented Apr. 13, 1915.

4 SHEBTSSHEET 1.

TRACTOR.

APPLICATION FILED JAN-30, 1913.

Patented Apr. 13, 1915.

4 SHEBTSSHEET 2.

TRACTOR.

APPLICATION FILED IAN-30. 1913.

191915,?0 Patented Apr..13,1915.

I GEORGE C. JJETT, 0F GARY, INDIANA.

TRACTOR.

wearer.

Specification of Letters Patent.

Patented a is, for a.

tiriginal application filed March 2, 11912, Serial Ito. 681,237. Dividedand this application filed January 30,

1913. Serial No. 745,107.

T all whom it may concern:

Be it known that I, GEORGE C. Jn'rr, a citizen of the United States,residing at Gary, in the county of Lake and State of Indiana, haveinvented certain new and useful Improvements in Tractors, of which thefollowing is a specification, reference being had to the accompanyingdrawings.

My invention relates generally to improvements in vehicles, and moreparticularly to their application to the class of traction engines.

My invention has for one of its objects the provision of an improvedtractor particularly' adapted for service in soft and miry ground whichis simple in construction and I ting a reduction in the size of theplanes be operation, and in the arrangement ofits parts; another objectis the provision in a tractor of novel means to obtain a broad endlesschain tread-upon which the entire weight of the tractor is carried andthe weight evenly distributed over a large area of ground by means ofthebroad planes thus obtained; another object of my invention is to providean improved interlocking.

Figure 2 is a plan view of the frame members.

Figure 3 shows a side elevation of Figure 2 with all the members abovethe broken line sectioned on dotted line IIIII I of Figure 11.

Figure 4 is a vertical section drawn on the line IVIV of Figure 1.

Figure 5 is a perspective view of the tractor asto appearance whenassembled.

F lgure 6 is a plan View of the complete structure.

Figures 7 and 8 are side and rear elevatlons respectively of the gearcasing, portions of the chain tightener being disassoarrangement of thebearing wheels within the chain tread members permitting the closeassociation of a large number of bearing or contact points with theplanes of the chain tread member, thereby preventing buckling of chainplanes, and also permittween their bending points to obtain acorresponding increase in the number of sprocket'chords; together withnovel means designed to obtain constant rather than variable rotation ofthe chain tread.

A further object of my invention is the provision of means adapted toproperly adjust the tension *of the chain tread. A still further objectof my invention is the provision of a tractor which delivers the highestpossible efliciency of the motor power represented in the pull at thedraw bar in ratio to its weight, without disturbing or packingcultivated ground. p 'llhesetogether with such other objects as mayhereinafter appear or are incident to my invention I; attain by .rneansof a con- 'embodying in struction illustrated in preferred form; in

the accompanying drawings, wherein:

Figure 1* is a front elevation of the tractor tread rerhoue from one.side of the machine.

invention, with the chain ciated in Figure 8 to illustrate theirrelation with the gear casing. Y

F1gures 9, 10 and 11 represent plan,'long tudinal sectional andtransverse sectional views of the side girders respectively.

In disclosing my invention I provide a main frame. A comprising. frontand rear transverse girders 12 and 13 respectively which are bolted tothe under sides of longitudinal angle members 14;, and to the uppersides of longitudinal bars 15, both of these longitudinal members beingextended rearwardly to form cantaliver beams which support the operatorsplatform 16 as shown in Figures 5 and 6.

The numeral 17 indicates a gear case. rigidly secured to and supportedcentrally above the frame A by the channel member 18 fast on the rearirder l3, and by the upwardly extending ront girder truss 12 insupporting engagement therewith. Mud guards 19 are bolted tothe angles14 and positioned on both sides of the gear case 17, and are furtherbent outwardly to provide horizontal plane surfaces 19 the preferredlocation for a suitable source of power, as the motors 20. In supportingengagement the gear case 17 transmitting power from the motor 20 to thetransmission mechanism B which is associated with a differentialmechanism in the gear case, which difi'en ential is actuated by a gearshaft 25 which receives rotation from the steering mechawith the gearcase 17 are angle irons 21 and integrally therewith, and is furtherprovided with a similar journal box 28 centrally positioned intermediatethe boxes 28 all affording alined bearings for a divided axle 29. Theouter journal boxes are effectually bracedby the channels 30, which arebolted to their outer vertical faces and run diagonally forward and arerigidly secured to the forward girder The journal box 28 is braced'bythe brace rod 31 which extend upwardly and are bolted to the rigidgearcase 17 To give further rigidity to the channels 30, and to otherchord members of the frame, the channels are securely bolted to thelongitudinal bars 14 and 15.

()n opposite sides of ning forward parallel with each other are sidegirders 32, pivotally mounted on the outer journal boxes, each girderhaving an upwardly inclined rear portion provided with an eye adapted toreceive the pivot pin 1; 33 positioned in the journal box.

The central j ournal box 28 similarly provides a bearing for a pivot pin'33 in alinement with the pins 33, which pin 33 forms the pivot for therods 34 which extend dita vergently forward to a point wherethedepending tapered ends are received in'holes 35 cored in the sidegirders 32 and secured by the nuts 36. If desired the hole whichreceives the tapered end of the brace rod is may be cored large enoughso that intervening space may then be filled in with Babbitt or othersuitable low fusing metals, thus affording easy and exact alinement ofas shown in Figure 2.

the frame A and runthese parts. The taper endof the rods and,

the nut permit ready removal. liletween the mainhframe A and the sidzegir ers 32 are. weig t carrying sprin s 3 each bolted a t its upper endto one o f the: outer extremities of front girder 12, the 5 lower end ofthe spring being bolted to the girder andfirmly positioned in a seat 38formed in the upper surface of the girder. Keyed to the-divided'axle atpoints intermediate the inner and outer journal boxes tare drivensprockets 39' connected to'. the.

drive sprockets 26 and 27 bjrendless drive chains 40,-and similarlymounte'don the axle are chain tread sprocket wheels 41 positioned onboth sides of each outer journal 5 box 28. Thesprockets 39 and 41'havetheir number of chords,

chordsof 39 andetl peripheries made up of a series of chords, and Ipreferably provide them with an equal or approximate chords, and locatethe chords with respect to each other so that the sprockets may be ontheir longest, or shortest, radii at the same instant.

At the forward end of the side girders 32 are journal boxes 42 hayingbearings for idler chain tread sprocket wheels 41, which together withthe sprocket wheels 41 carry an endless chain tread D, and which latterincludes the broad level planes 43 pivotally connected together to serveas a track for the weight carrying or bearing wheels-44 journaled in theside girders 32, as more fully described hereinafter.

In a co-pending application for Letters Patent, bearing the SerialNumber 681,237, and filed March 2nd, 1912, I show my preferredarrangement of transmission gearing in which I obtain varying forwardand reverse speeds, and this gearing is connected to a differentialmechanism actuated by a steering shaft (as c in Figure 4) to'obtainopposing movement of the chain tread members on either side of themachine to turn the tractor in its own length, or with the transmissioncut. in to turn the tractor in either direction on any desired arc.

From the description thus far made it will be apparent thatinasmuch asthe girders are pivotally mounted on the frame at their rear ends, thechain treads have vertical movement within the limit of-elasticity ofthe weight carrying tension and compression springs 37, the three pins33, 33, 33 forming the axis'of this permitted vertical movetoo mentwhich'is provided to take care of inmet with.

Referring now again to the driven sprockets 39 and sprocket wheels 41, Ihave said that their respective peripheral chords are equal in numberand similarly located, and my purpose is to overcome the objectionablefeature of a variable speed due to variable radial distance of the chainto the axis of rotation of the driving sprocket. As the angle betweenthe drive chain and chain tread is fixed, I obtainconstant andcontinuous velocityin the chain tread, in that the drive chain'members.on driven sprockets 39 and tread chain members on sprocket wheels 41are driving on their longest radii at the other instant; which statingit in other words, that sprockets 39 and 41 'are solo-' cated ontheshaft 29 that the drive chain'and chain'tread come tangent to theperipheral 1 25 at the sameinstant. .It

is considered important and preferable that" the number of sprockets in39 be equally divisible by the number of chords thereon. I I Thepreferred means of engagement between sprocket wheels 41', 41 and thechain tread members is to alternately locate the sprockets on-the chordson each pair of associated sprocket wheels" and. to similarly provide analternate arrangement of slots 45 in the chain tread, in other wordseach plane 43 has only one slot in order to eliminate as far aspossible'any disturbance of cultivated ground as will be understood.

The front journal boxes 42 are secured to the upper surface ofits-respective side girder 32 by bolts 46 passing through elongated orslotted holes 47, so that on loosening up the bolts 46' the journal boxis capable of longitudinal adjustment through the set screws 48 providedto tighten or otherwise adjust the chain tread, in order to remove itor'take up for wear. Afteradjustment, the

bolts 46 are tightened, andto insure perfect" longitudinal alinement forany position of the journal box on the girder, complementary ways areprovided on the journal box and in the girder as shown at 49.

Referring now more particularly to Figures 9, 10 and 11, it will be seenthat the side girders furnishthe journal bearings for the bearing wheels44: which have what" if term an interlocking arrangement with eachother, whereby I obtain a greater number of wheel hearing or contactpoints with the chain tread within a minimum space, and with a minimumof frictionv at such points due to the greater wheel circumfer- 'doesnot subtract from the desired large bearing surface of the chain tread,for by arranging the associated pairs of sprocket wheels i leand ll -oneither side of the j ournal boxes, which-in this instance act as spacingmembers between the members of each pair, I obtain a series ofsuccessive broad planes pivoted together at their edges to form acomparatively solid and endless track for the weight carrying or bearingwheels toroll on, and thus form what might be termed a platformpossessing suficient breadth to evenly distribute the'weight of themachine over an extended area, so that the tractor can readily operateover heavy ground where an ordinary traction machine would mire.

The bearings 51 provided inthe web of the girders 32 are preferablytaper bored'to J fore delivered in drawbar pull.

receive correspondingly'tapered axles 52 of that the greatest diameterof the wheels can be suitably placed in the shortest distance betweentheaxes, thereby ultimately. obtaining a greater number of wheels of alarger circumference; a greater number of points of-contact with theendless track within the shortest distance between outer contact points;and with a minimum of friction en gendered.

To'obtainthis interlocking arrangement ll providethe interchangeablehubs 53 which of Wheels, and against the outer sides of the adjacentpair of wheels, the wheels being secured on. their axles by the nuts54:- It will be noted that axles, wheels, hubs, and nuts are similar'inevery respect, except in the method of their arrangement. In mypreferred construction the distance between points of contact of weightcarrying wheels is less than the length of a link member or plane. 3

The side girder web is cored to provide oil. pockets 4 55 which extendvertically through the bearings, and are designed for the insertion ofoily waste to thoroughly lubricate the bearing wheel axles. The severaloil pocket openings in the under side of the the-bearing wheels 44:, andare so located I .are alternately-positioned on successive axles to bearagalnst the inner sides of one pair girder are covered by one continuouscover plate 56 which performs the double duty of afiording the bottomfor the'oily pockets and also acts as the bottom chord member of thegirder, being secured thereto in any suitable'manner. 7

The gear case is provided with a removable cover and is made oil tightfor the'purpose of filling it sufliciently with oil so as to give acomplete and continuous oiling system to the transmission anddifi'erentia-l mechanism located therein.

From the foregoing, it will be apparent that my tractor is particularlyadapted for traction purposes through rough or miry country by reasonofthe broad planes af forded in the extended chain treads or platforms,whichfurnish and bridge. its own road across furrows and ditches. Byhinging the chain treads at the rear end of the tractor, each is freeand independent of the other to find its own proper alinement on theground. The entire arrangement is com pact and of simple construction,and all members carrying the heaviest loads are arranged so as to takecare of the loads in the direction of the forces along which they oc-The highest eficiency ,of the motor power used'is obtained by making allmembers which come in contact with the ground a part of the Otheradvantages will readily those skilled in the art.

riving force which is there-- a ear to PP ce Having thus described myinvention and 'illustrated its use what I claim as new and desire toobtain by Letters Patent is the following LA tractionmechanismcomprising a main frame, traction.,wheels carried by saidframe, a traction girder intermediate the Wheels, an endless belt passedaround said wheels, composed of pivoted tread members,

and means for preventing buckling of the tread members on their pivotsin the travel of the belt comprising a plurality of interrelated bearingwheels mounted in the girder alternate'overlapping and interfittingbearmain frame, traction wheels carried by said frame, atleast one ofwhich has a periphery composed of a series of sprocketed chords, a

traction girder intermediate said wheels, an

endless traction belt passed around said wheels composed of pivotedtread members adapted to engage said chords, and means mounted in saidgirder for preventing buckling ofthe tread members on their pivots inthe travel of'the belt comprising a group of ing wheels arranged in saidgirder with ref erence to said chords and tread members wherebywheels ofthe group severally bear upon adjacent underlying tread members.comprised within the lower stretch of belt to maintain thealinement ofthe belt. I

3. A traction mechanism comprising a main frame, traction Wheels carriedby said frame and comprising associated pairs of spaced driving andidler wheels, an endless I belt passed around said wheels composed ofbroad pivoted tread members adapted to bridge the wheels of each pair inthe travel of the belt and each having a breadth greater than theirlength, a traction girder intermediate each pair of wheels, and aplurality of bearing wheels mounted in the girder and arranged thereinin a staggered inter-relatlon, with one another to bear upon treadmembers in. the lower stretch of belt in such amanner that the distancebetween the [points of contact is less than the length of'a treadmember. H X

4. A traction mechanism comprising a main frame, traction wheels carriedby said frame, a traction girderextending. longitudinally between thewheels, an endless :belt

l in said passed around said Wheels and composed of pivoted treadmembers, and means mounted girder for preventing buckling of. the treamembers in the travel of the-belt comprising a plurality/of bearingwheelsarranged in a staggered inter-relation lvvith each other and withthe traction wheels, said wheels severally bearing on adjacent treadmembers composing the lower stretch of belt with the distance betweenpoints of contact slightly less than the length of a tread member.

5. 'In a tractor, the combination of a frame, a driving wheel journaledin said frame, an idler wheel, a traction belt passing around saidwheels, a traction girder pivotally mounted on the driving wheel withits forward end in supporting relation with the idler wheel and providedwith bearing wheels adapted to bear on the lower stretch of belt, and aspring connection interposed between the girder and frame and at a pointadjacent the idler wheel.

6. In a tractor, the combination of a frame, a driving wheel journaledin said frame, an idler wheel, a traction belt passing around saidwheels, a traction girder pivotally mounted on the driving wheel andhaving its forward end in supporting relation with the idler wheel, anda bracin member for the girder having its rear end pivoted in the frameand on a line substantially coincident with the pivotal axis of thegirder.

7. In a tractor, the combination of a "frame having a drive axle, a pairof rear driving wheels mounted in a spaced relation on said axle, a pairof associated front idler wheels, a traction belt passing around bothpairs of wheels, a traction girder supporting the idler wheels andhaving its rear end pivotally mounted at a point intermediate the pairof rear driving wheels,a spring connection interposed between the girderand'the frame at a point removed from the pivoted end of the girder, andbearing wheels mounted in said girder to bear on the lower stretch ofbelt intermediate the driving and idler wheels.

8. In a tractor having a frame and a chain tread member disposed fortravel along the ground, of a traction mechanism comprising a sprocketwheel and a sprocket gear mounted in the frame for synchronous rotationmovement and having their sprocket chords located similarly with respectto each other, said sprocket wheel being adapted-to operatively engagesaid chain tread member, and adrive member located in said frame withreference to the chain tread member and engaging said sprocket gear,all'so arranged whereby to impart a constant velocity to the chaintraction memher in its said travel.

9. In a tractor, the combination with a frame and a chain tractionmember mounted adjacent the side of the frame for travel alongthe'ground, of a driven axle mounted in said frame, a traction sprocketwheel on the axle operatively engaging said chain traction memberandformed with a chordal .,ber in operativerelation with said drivensprocket gear and disposed inthe frame at a fixed angle with respect tothe line of nor-' mal travel of the chain traction member.

10. In a tractor, a traction mechanism comprising a frame, adifferential and transmission mechanism mounted in a portion of saidframe, a steering means in operative relation with said mechanism,traction devices located adjacent the sides of the frame for travelalong the ground comprising a traction belt and a driving wheel adapted.to engage with said belt to drive the belt, transverse shafts disposedin alinement in another portion of said frame and each carrying at itsouter end one of said driving wheels and independently operableconnections between said mechanism and each shaft, substantially asdescribed.

11. In a tractor, a traction mechanism comprising a frame, tractiondevices located at the sides of the frame and each comprising a tractionbelt and a driving wheel engaged with said belt, transverse shaftsarranged end to end in line with-each other in the frame and eachcarrying at its outer end one of said. driving wheels, a transmissionand differential mechanism removed from said shafts, a sprocket gearmounted adjacent the inner end of each shaft to have synchronousrotative. movement with its contiguous Wheel, and independent driveconnections extending between the said mechanism and each sprocket andlocated at an angle with reference to the line of travel of saidtraction belt, substantially as described.

12. Ina tractor, a traction mechanism comprising a frame, tractiondevices located adjacent the sides of the frame and each comprising atraction belt and a driving wheel adapted to engage with said belt toactuate it, transverse shafts disposed in said frame and each carryingat its outer end one of the said driving wheels, a sprocket gearmounted'on each shaft to rotate with its adjacent wheel, a differentialmechanism in said frame removed from said shafts, and

ing between the said mechanism and each sprocket, substantially asdescribed.

In testimony whereof, I have hereunto signed my name in the presence ofthe two subscribed witnesses.

' GEORGE C. JETT.

Witnesses W. HERBERT FOWKES, MARGARET MOORE.

7 independently operable connections extend-

